Inkjet recording apparatuses and image reading apparatuses are known as electronic apparatuses including motor control devices for driving motors. An inkjet recording apparatus scans a recording head by driving force of a motor, and an image reading apparatus scans a reading unit by driving force of a motor.
Driving force of the motor includes a so-called torque ripple (cogging torque). The torque ripple is transmitted to a carriage via a timing belt. While the moving speed of the carriage is controlled, for example, using a speed profile prepared beforehand, it is changed by the influence of the torque ripple. The cycle of occurrence of the torque ripple is determined by the structure of the motor. To remove the influence of the torque ripple, a feed forward (FF) control method for adding a signal for suppressing the torque ripples has been proposed.
In a recording apparatus disclosed in Japanese Patent Laid-Open No. 2005-178334, positions where torque variation occurs are measured by speed variation of a carriage, a correction table for correcting a speed driving command is generated, and the carriage is driven according to the correction table. In the correction table, a driving command value is set at a low value when the speed detected by an encoder is higher than a target speed, and at a high value when the detected speed is lower than the target speed.
However, the waveform of the torque ripple includes torque variation having various frequency components, and the frequency components are influenced by one another. Further, there are individual differences in the magnitude of the torque variation including the frequency components among electronic apparatuses even when the electronic apparatuses are of the same type. Therefore, even if the technique of the above publication is applied, it is necessary to perform many measuring and adjusting operations in order to suppress torque variation containing various frequency components, and this takes much time and trouble.